1. Field of the Invention
The present invention relates to a method of electrically connecting shields that are contained in a plurality of extra fine coaxial wires respectively, with a common conductive member.
2. Related Background Art
The extra fine coaxial wire includes a center conductor extending along a predetermined axis, an inner insulator provided on the outer periphery of the center conductor, a shield provided on the outer periphery of the inner insulator, and an insulating jacket provided on the outer periphery of the shield. The center conductor and the shield are comprised of conductive metals, for example a tin-plated copper alloy, respectively. The inner insulator and the insulating jacket are comprised of an insulating resin, for example PFA and PET, respectively. Then, the outer diameter of the insulating jacket is about 0.25 mm to 0.5 mm. Since such an extra fine coaxial wire has a very slim outer diameter, it is suitable for use when connecting electronic components electrically in a small electronic apparatus.
When connecting the shields in the plurality of extra fine coaxial wires electrically, first, in a portion in the longitudinal direction of the extra fine coaxial wire, a part of the insulating jacket is removed by, for example, irradiating with laser light. As a result, the shield is exposed. Further, parts of the shield and the inner insulator are removed, and thereby the center conductor is exposed. At this time, the exposed shield is expanded. As a result, it is likely to cause a connection failure among the shields in the plurality of extra fine coaxial wires. For example, Japanese Patent Application Laid-open No. 2005-328696 (Document 1) and Japanese Patent Application Laid-open No. 2001-307556 (Document 2) disclose the technologies that are intended for solving such a problem.
The technology disclosed in Document 1, first, in each of the plurality of extra fine coaxial wires, a part of the insulating jacket is removed and thereby the exposed shield is covered by a solder layer; the solder layer and the shield are cut off at a predetermined position of the solder layer; and the solder layer and the shield from the cut position to the top end are removed together. Then, the conductive member common to these plurality of extra fine coaxial wires is fixed onto the respective solder layers of the plurality of extra fine coaxial wires that are not removed and remain, and thereby, the electrical connection among the plurality of extra fine coaxial wires is made. On the other hand, Document 2 discloses the technology by which the respective shields in the plurality of extra fine coaxial wires that are exposed by removing a part of the insulating jacket and a ground bar (a conductive member common to the plurality of extra fine coaxial wires) are soldered to form a connection, thereby integrating the plurality of extra fine coaxial wires. Also, the technologies disclosed in both of Documents 1 and 2 are intended to connect electrically via the conductive member common to the respective shields of the extra fine coaxial wires by soldering and thereby prevent the shields from expanding during the connecting work.